Month: November 2015

There have been a few posts speculating on the future of VSAN and I for one am looking forward to it with great anticipation. However, I don’t think VMware really know what a hugely transformative technology VSAN could be.

I was lucky enough to attend VMworld 2015 and luckier to be invited to the VSAN pioneer summit, which gave us a real in-depth look at the future of VSAN. I liked what I was seeing but about an hour towards the end of the allotted time I put my hand up and asked why there were no NAS features planned for the future release. I mean it makes sense doesn’t it? Where’s NFS, where’s SMB? I know a linux architect who would love to see this come in.

If you really want to do the software defined storage thing then really go for it. NSX is the current favourite child. its being pushed everywhere, including presence into “competitors” such as AWS. So where’s the love for VSAN? Push this technology and it will really change the datacenter.

First Thoughts.

What if VMware made a VSAN only cluster, no VM’s allowed only storage exports. This would put them in direct competition with Storage vendors and would greatly reduce the cost for storage in the datacenter and allow for a huge amount of flexibility for businesses of all sizes. lets explore this idea more!

Folders (native on the file system) or VMDK’s

VMDK wins. I would think that using VMDK’s instead of folders would be a much better idea. There would be no real changes needed to the VMFS file system to accommodate a much more granular permission structure that would be required by SMB. ESXi could mount the VMDK and write any file system in there. VMDK’s can be accessed by multiple ESXi hosts.

NFS3 – NFS4 – SMB2.x – SMB3

We already know that NFS4 and SMB3 can take advantage of multiple IP addresses (hosts) to provide multi-channel and VMware clusters are, quite frankly, an incredible implementation of clustering technology. Mounting the VMDK to multiple ESXi hosts would allow the data to be taken advantage of by NFS4 and SMB3 compliant hosts.

SMB2.x and NFS3 prefer to access data through a single IP address or hostname. Now this is easy to implement immediately but if you want to add a bit more intelligence around it, some kind of construct that has a virtual IP that could move between hosts or something like the virtual IP address technology from Log insight clusters. Easier said than done I know but still should be considered.

Redundancy and performance

Kinda obvious, i know, but redundancy would be taken care of by VMware clustering technology. three or four hosts and that’s that taken care of.

Performance on the other hand could be very interesting topic, a complex topic, but still interesting. I would guess in the thousands of IOPs. There would be many factors to consider. Network speed, controller card, SSD speed, SSD size, and so on and so forth. In a future post I’ll look at this again.

Licensing

As this is only intended to be a storage service the licensing should be one ESXi-VSAN license (I’ve guessed it to be £1,500 but could be as high as £2,000, which I’ve also given as a cost per TB below)

Total Cost

So this is interesting and I’ve decided to look at a couple of real world examples below.

Dedicated Storage Appliance

I have a quote from a major vendor for £198,409.45. This figure gives us 48TB of HDD storage in 64 SAS disks and 9TB of SSD storage in 8 SSD disks (these figures are usable). For this project we decided to use the SSD as a caching layer. As you would expect from an enterprise storage system it has a good deal of redundancy built-in with 4 nodes to manage the storage and 8 x 10GB Ethernet ports. All in, not bad for the price point and a good system all round.

Dedicated VSAN Cluster

Putting together our VSAN only node, to compete on numbers, I would size it like this: Looking at an HP DL380 Gen9 with one CPU (E5-2623) 32GB of Ram. Two disk pools with 1 x 800GB SSD and 7 X 1.2TB SAS disks each, giving us 1.6TB of SSD cache and 7.5TB of SAS storage (again these figures are usable based of a default VSAN storage policy of 2n). Two 10GB Ethernet ports.

To get the equivalent amount of usable storage as the popular storage vendors array we’d need 7 VSAN nodes.

So for the costs:

Items

Storage Vendor

VSAN

Nodes

4

7

10GB Network

8

14

SSD Cache Size

9.2TB

10.5TB

Usable SAS

48.5TB

52.9TB

Cost per system

£198,409.45

£109,320.40

Cost per TB

£4,090.92

£2,066.55

Note 1: I have estimated the cost of the VSAN license at £1,500. If the license were £2,000 then the cost per TB for VSAN would be £2,132.71.

Note 2 : (To be fair) The Storage vendor has extra goodness built-in to accelerate workloads and the hardware will be optimised and custom designed to do nothing but server data.

The above figures, which speak for themselves, are all based on real quotes and would be for an enterprise deployment.

If VMware really wanted this to be everywhere they could address smaller shops by allowing a single node VSAN. Why not; that would allow anybody to get a foot in and expand as their business grows.

So VMware, when will this be a reality for us?

Please let me know what you think and it there are any glaring errors. I’m also happy to discuss any of the above.

I was introduced to mind maps at school as a way to take notes during class but never really worked with them. Earlier in the year, while studying for my DCD I happened to see somebody at the library referring to a mind map while they were working.

That got me thinking; mind maps are quite personal as in you put it together. In effect, its your mind map, its put together in a way that you can reference information clearly as it relates to how you have stored it in your mind.

I was going through Jason Grierson excellent DCD 5.5 Study pack at the time and decided to create a series of mind maps from the info. This allowed me to very quickly go and look for the detail I needed. If you are studying towards your DCD the DCD 5.5 Study pack is a really good collection of information that you should download and go through.

Lets take a look at the map I created for the three different types of designs that VMware references. This is quite a small map but allowed me to quickly get the differences between Conceptual, Physical, and Logical designs.

The next map looking at the four design factors has a bit more detail giving examples and definitions of risks, assumptions, constraints and, requirements.

And as a better example this map dives into the design requirements of manageability, recoverability, availability , security, and performance. Still not a big mind map by any means (the ones I’ve been working on for my VCDX are getting a bit on the big side).

Many of the maps I create will only ever be seen by me. I use them as references when working on designs. Actually I’ve been using them for any projects I now have, both professional and personal. I’m looking at doing some work on my kitchen and this tool has helped keep all my ideas together in a way that I can easily reference them.

The reason I chose to show these maps is to give you another tool when putting together designs and working out what the client/your boss is trying to get you to do.

The software I use to create my maps is Simplemind. It’s avaliable for PC, MAC, Android, and IOS. There is less featured free version for IOS and Android. The map can be shared through all platforms via Dropbox.

I have a confession to make. I am a Virtual SAN junkie. From the performance, to the expandability, to the simplicity, it’s an amazing product. The whole concept makes me wonder why the big storage players didn’t come up with the idea first.

Looking forward, the future forVSAN is very bright. This is a massive development and I think it will have wider reach than NSX. It’s so easy to get up and running, that a business of any size could spin it up with little effort. Just don’t forget to validate against the HCL.

Now, if you are happy with that and don’t really intend to do much with it then click away now, but if you want to understand more about the technology you are running then Duncan Epping and Cormac Hogans book Essential Virtual SAN is one of the best resources you can sink your money into.

Before we carry on, one thing to note is that this book is written around VSAN 1.0. While VSAN 6.1 is out it’s not 6 versions further on but more like 1 full release and 1 point release further on. VMware changed the version numbers to reflect the vSphere versions. So that said, this book isn’t obsolete. Far from it. The new versions really only build on what is already an amazing platform. It is still completely relevant, just missing some new goodies, like stretched clustering and info about the updated file system. For all the updated info have a crawl through Cormac’s blog and the VMware Technical Papers.

I’ve ready a couple of Duncan’s other books, the vSphere 5.1 Clustering Deep dive written with Frank Denneman for example,and found them to be very easy to read. Often a book aimed at techies can be very dry, which makes then a struggle. Cormac is Mr VMware Storage and his blog, read by many people, is always informative and good to read.

Essential Virtual SAN on the other hand reads well. The sections are well thought out and the book takes you from introducing VSAN all the way through to using the vSphere ruby console to look in real detail at what the individual disks are doing.

The authors do state that this is not a starters guide, while they are right, I found this book to be more than enough for both beginners and the more experienced to really find useful.

Duncan and Cormac’s enthusiasm for VSAN really comes through in this book. Obvious, I know, when you look at their blogs, but it does feel like this is more than a 9-5 for them.

At the office we have recently deployed VSAN. This went through the usual steps of putting it in engineering, running a successful POC and finally getting senior management buy in to roll it out. This book was a huge help in helping me boost my knowledge and fielding any concerns raised by the business.

I did attend the VSAN deploy and manage course, this book is better.

The future for VSAN is bright and, to me it’s clear that this should be on your roadmap, if it isn’t already.

Carrying on with my Graylog posts, the following will give you an introduction to creating a basic but functional dashboard.

Why do you need a dashboard? Well you can view a number a widgets very quickly which can all be configured with separate search queries. What’s really convenient is that it’s your dashboard, not one that the vendor thinks you will need. Every environment has different requirements. Perhaps you are tracking iSCSI disconnects and want to see a count of the number of iSCSI errors you are getting prior to the event, maybe want to track how many logs vpxa generates, or list the amount of port scans you are getting on your external firewall. It’s really defined by you.

Browse to your Graylog server and login.

Click on Dashboard on the Menu across the top.

Once the Dashboards tab has opened click Create Dashboard.

Give your new Dashboard a name and description.

You now have a brand new empty dashboard. lets get some widgets generated and add them in.

Click on Search in the menu bar and in the search field type something that you’d like to keep an eye on. For this purpose I’ve chosen the vpxa. It’s noisy and will be a good example.

This will return, a histogram and a bunch of messages.

Lets add the histogram to the dashboard. In the histogram pane click on Add to dashboard and select the dashboard you want to add the histogram to.

And lets add one more. In the Fields pane, expand Messages and click Quick Values. Then in the Quick values for message Click Add to dashboard and select your dashboard.

Go through the various fields and widgets and add what you think will be useful.

Back to our dashboard. Click on Dashboard in the Menu across the top and then click on the name of the dashboard you just created.

You’ll now see the widgets you’ve added to your dashboard. You’ll also see three buttons, Update inbackground, fullscreen and unlock/edit. To rearrange your widgets click unlock/edit and move them around as needed. Update in background keeps the widgets live and fullscreen puts the screen into a display mode which could be useful to display on screens around the IT department.

Once you are done move things around click lock to take it out of editing mode.

The above does go through creating a very basic dashboard by once again this demonstrates how useful Graylog really is. If you are looking for log monitoring you will be in a safe place with Graylog. The flexibility and scalability, absolutely compete with, and often exceed, the larger paid for rivals.

The first of the VCDX defense dates for 2016 have been announced and in the last week a new round of VCDX’s have received their emails and a big congratulations to all of them

I’ve been looking forward to the new 2016 dates for a while. This gives me a time frame to get all the requirements together.

If all goes according to plan I’m hoping to defend in the last week of April but that means I need to submit but the 11th of February. which is only three short months away and I still have a huge amount to get together.

As I work through various part of my design I’ll be tracking my progress through this blog.

Designs that are your own are easier to justify, or are they? Take one of your own designs (as I’ve done with this one), and try to look at it with fresh eyes. It’s yours, yes, but can you really quantify every decision to a third-party. Why have you chosen to ignore LACP, why aren’t you using resource pools, why have you used the windows deployment of vCenter server instead of the appliance. iSCSI vs NFS. 5 Hosts, really, why not 3 larger hosts instead? Want to bring in VVOLs, have you spoken with the storage team to find out if it can fit with their vision? Why, Why, Why?

All of the above and more needs to be worked through. The foundation of my design is one that I have done for the company I currently work for. It is a two DC deployment with SRM to replicate between them. My submission will be partly fictitious as I want to take what I currently have and update it. I’ll need to go through and look at every decision and document it.

I understand that this will be a huge undertaking but I am looking forward to it. Most importantly I have the support of my family.